The chemokines are a family of small, proinflammatory cytokines, with potent chemotatctic activities. Chemokines are chemotactic cytokines that are released by a wide variety of cells to attract various cells, such as monocytes, macrophages, T cells, eosinophils, basophils and neutrophils to sites of inflammation.
Chemokine receptors, such as CCR2 or CCR5 have been implicated as being important mediators of inflammatory and immunoregulatory disorders and diseases as well as autoimmune pathologies such as rheumatoid arthritis and atherosclerosis. Accordingly, agents which modulate chemokine receptors such as the CCR2 and CCR5 receptor would be useful in such disorders and diseases.
In particular it is widely accepted that numerous conditions and diseases involve inflammatory processes. Such inflammations are critically triggered and/or promoted by the activity of macrophages, which are formed by differentiation out of monocytes. It has further been found that monocytes are characterized by, e.g., a high expression of membrane-resident CCR2, whereas the CCR2 expression in macrophages is lower. CCR2 is a critical regulator of monocytes trafficking, which can be described as the movement of the monocytes towards an inflammation along a gradient of monocyte chemoattractant proteins (MCP-1, MCP-2, MCP-3, MCP-4).
Therefore, in order to reduce macrophage-induced inflammation, it would be desirable to block the monocyte CCR2 by an antagonist, so that the monocytes can be less triggered to move towards an inflammation area for conversion into macrophages.
CCR2 antagonists, which modulate chemokine receptors such as the CCR2 and CCR5 receptor are disclosed by WO 2010/070032.
Based on the aforesaid there is a need for providing effective antagonists for CCR2, which are pharmacologically acceptable and which show selective activity for Chemokine receptors CCR2, whereas an activity for Chemokine receptors CCR5 is reduced.